Despite that hopeful report, however, higher-order multiple births (defined as three or more babies born together) are dangerous for babies and the mother. Infants born prematurely face the risk of breathing problems and brain injuries that may cause permanent disability. Problems in premature babies, including learning disabilities or cognitive delays, are often not apparent until years after their births.

The American Society for Reproductive Medicine and the American College of Obstetricians and Gynecologists say “doctors should be making efforts to curb these higher-order multiple gestations,” said Dr. Geeta Swamy, an assistant professor of obstetrics and gynecology at Duke University. “But it really is still up to the individual physician. There aren’t any laws or legal ramifications to it.”

The babies could have been conceived through in vitro fertilization, in which eggs and sperm are combined in the lab and a specified number of the healthiest-looking embryos are transferred to the uterus. That scenario seems unlikely because fertility doctors are asked to adhere to strict guidelines that limit the number of embryos transferred. As a result, higher-order multiple births resulting from in vitro fertilization are uncommon.

A more likely scenario is that the mother of the octuplets received infertility drugs in a procedure called controlled ovarian hyperstimulation. The treatment, which is typically used to achieve pregnancy in women who do not ovulate, stimulates the ovaries to produce a number of eggs. As the eggs near maturity, the patient usually has artificial insemination.